trying to improve poor idle.

Pulled the dist. I had lowered the engine to put the trans in and it had rested on the vac can. Little loose. Tightened that up, put it back in.

Checked the PVC valve, found it had a crack in the housing. Replaced it . Cranked it, moving the dist, til it fired up. Choke was fully closed but the idler was around 8-900 rpm. Was runnig OK, just not at the 15-1800 rpm I usually get at startup.

Let it warm up, kicked off the choke, and got the idle to around 750. (took a lot of idle screw for that). Still running good. In fact, very good.


Pulled the vac hose to check ,and pulled 15-16. Wow. I had learned to live with the fact that 8-10 was the best I would ever get. Happy with that too.

I did notice the breather hose to the air cleaner wasn't pulling any vac. Need help with that one.


Took it out for a test drive.(thats what I tell my collector ins. company). Ran great in town, decided to take it for a quick highway test. Got up the the usual 65-70 where the vibration would start. No vib.... up another 20 or so mph's... still no vib. I had this problem pegged to a drivetrain/ rear issue. The shifter would rattle like you wouldn't believe. Fixed it???


Not that I'm complaining, but any thoughts on any of this stuff.



BTW... 1970 350-350hp, new edelbrock q -jet 1901(real dog) fresh engine rebuild, MSD dist, box, M-21, 370.......

 

i would guess that maybe the distributor was in wrong and you corrected it when you pulled it out.

 

Probably. And re: the valve cover vent having no vacuum? It's not supposed to!

 

Thanks for the replies.

I thought the breather connected to the flame arrestor in the air cleaner sucked air. Maybe not.



Funny you both say distributor.The dist went in a little different. I wanted to ease the tach cable tension a bit. Even with a slightly different position though, I set the timing the same as the old position. Would the physical location of the dist. have any effect if the plug locations were adjusted to allow the exact same timing mark?

 

That carburetor is jetted lean for emission reasons. Especially for a 350/350. That is why you're having to run the idle mixture screws so far out. If you go a little richer on the idle, off idle and cruise metering it will feel a lot better.

BigBlockk

Later.....

 

Bigblockk


Someone else told me about the lean jetting on that carb. Secondaries only open about 30 -40%. Until I get my original back from rebuild, I'll try adjusting richer. Thanks